Method of making envelopes



Feb. 6, 1968 H. HORNUNG METHOD OF MAKING ENVELOPES- 2 Sheets-Sheet 1 Filed March 15, 1965 INVENT R z/vz/f ammw ATTORNEYS Feb. 6, 1968 H. HORNUNG 3,367,249

METHOD OF MAI \[NG ENVELOPES Filed March 1965 2 Sheets-Sheet z ATTORNEYS United States Patent Ofilice Patented Feb. 6, 1968 3,367,249 METHOD @F MAKING ENVELOPES Heimut Hornnng, Scarsdale, N.Y., assignor to F. L. Smithe Machine Company, Hue, New York, N.Y., a corporation of New York Filed Mar. 15, 1965, Ser. No. 439,816 18 Claims. ((Il. 93-61) ABSTRACT OF Til-1E DESiILOSURE In the manufacture of envelopes adhesive is applied at two successive stations to a stream of blanks moving in lapped relation. Where the seal flaps are trailing adhesive is applied to the bottom flaps which are first deflected in a direction opposite to the movement of the stream to expose marginal edges. Where the seal flaps are leading, adhesive is applied to the side flaps and the position of each blank is reversed end-to-end prior to securing the bottom flap.

This invention relates to envelope making machines, and has particular reference to the portions of the machine which operate upon the envelope blank after it has been cut and scored, that is, the portions applying the gum which secures the bottom flap to the side flaps, apply the seal flap gum and perform the various necessary folding operations to deliver envelopes ready for packaging.

In machines as they have been developed up to now, blanks have been collated, that is, arranged in accurate overlapping relation, with only the margin of the seal flap exposed, and the seal gurn applied by means of a continuous roller. As a limiting factor in the volume of envelopes produced in a given time is the tendency of the gummer to sling gum if its peripheral speed is too high, this arrangement permits the maximum number of envelopes to pass the gummer per hour while the gummer is operated at a safe peripheral speed.

Another point at which difficulty is sometimes experienced in envelope machines is those points at which an array of overlapped envelopes is accelerated, to separate the envelopes for folding the sides, either the top and bottom flaps, and also, of the application of adhesive to both the seal and bottom flaps. Obviously, adhesive cannot be applied to an overlapped array of envelope blanks to supply the seal and bottom flap requirements, as one or the other of the flaps has its adhesive receiving surface covered by adjacent blanks in the array. This being so, it has been customary to separate the blanks into a separated line of blanks, for certain operations, after which they may be arranged in an overlapping array suitable for another operation.

It is desirable, from the point of view of production and the size of machine required, to have a minimum of travel of the envelope blanks in serial as distinguished from overlapped array. It is also desirable to have a minimum of array-changing, involving accelerating and decelerating the envelope blanks, because of the complex mechanisms and adjustments which must be made to assure proper delivery of the blank as it passes from one array to the other.

In view of the above considerations, it is a primary object of the present invention to provide an envelope machine and method which performs the various operations required to produce an envelope with the envelopes traveling through the various parts of the machine in as overlapped an array as possible consistent with the operations being performed thereon.

It is a further object of the present invention to provide an envelope making machine and method in which there is a minimum of change of array of the blanks as they pass through the machine.

Referring now to the drawings:

FIG. 1 is a showing, in diagrammatic form, of a preferred form of the machine and method; and

FIG. 2 is a similar showing of a modified machine and method of the present invention.

Referring now specifically to FIG. 1, blanks 10, of rhomboidal configuration, are fed in spaced apart serial array to a series of pairs of rollers 11, 12, 13 and 14. These rollers deliver blanks 15 with the proper configuration and proper score lines to the collator 16. In the shown apparatus, rollers 11 and 12 form the notches or corner cuts, rollers 13 properly shape the ends of the side flaps and bottom fiaps, and perform the side scoring, and the rollers 14 score the blank at top and bottom.

The blanks are arranged by the collator in overlapped array, with the bottom flap leading and on the bottom surface of the array. The surface of the bottom flap which is to receive the adhesive is thus facing upwardly, but concealed by the preceding blanks.

Accordingly, means is provided to fold the bottom flaps to the rear. The bar or roller 17 is mounted to engage, or nearly engage, the surface of the blanks as they pass it. It can be seen that if the bottom flap is pulled downwardly, say by hand, as the first blank passes the roller 17, it will be folded over as shown in the array 18. The flaps of each succeeding blank will be folded back by the folding of the preceding flap, in a manner analogous to the turning over of a pack of playing cards lying in overlapped relation on a table, by the lifting and turning of the bottom card. The blanks then enter a gummer for applying gum to the bottom flaps, on the now exposed inner surface thereof. Preferably, the adhesive is of the type which is applied hot, and loses its tackiness when cools/:1 sufficiently to prevent adhesion. It is preferably applied by a form roller 19, that is, a roller with raised portions which in effect print a pattern of adhesive in the desired location on each flap as it passes between the roller 19 and the roller Zil. This results in a pair of properly disposed patches 21 of adhesive on each flap.

Beyond the rollers 19 and 20, the bottom flaps are unfolded, and placed in the position which they occupied as they left the collator 16. This can be most advantageously done by directing a current of air toward the bottom of the array and forwardly with respect to the path of travel of the blanks. This air current is sufiicient to bend the bottom flaps forward far enough forward to permit the finger 22 to engage the flaps and guide them into the bite of the rollers 23 and 24.

The envelope blanks will then be in the array originally produced by the collator 15. At the top of the array, the sealing flaps trail the body of the envelope blank, and the surface to be gummed is thus exposed.

The blanks are then led past the gumming station where sealing gum may be applied to the sealing flaps by means of a continuous roller 23 cooperating with roller 24, adhesive being supplied to the roller 23 by rollers 26 from a reservoir 27 in the usual fashion.

The adhesive is dried as the envelopes travel along the aligner 28, which spaces them slightly in order that they not adhere to each other, and accurately positions them for the next operation.

For the purpose of folding the side flaps in, the array is opened up to the extent shown at 30, by any conventional means. The opening need be no more than sufficient to permit each side flap to fold in without interference from the side flap of each adjacent blank. The corner cuts on the top and bottom flaps are ordinarily inclined, so that the space 33 can be quite small without the side flaps disturbing the top flaps of adjacent blanks. Any suitable folding means may be used, the conventional plowshare folder 31 being the most convenient.

The blanks now require their bottom flaps to be folded and stuck to the side flaps. This can be done by means of the mechanism disclosed in the patent to Abraham Novick, No. 3,116,668, dated Jan. 7, 1964. In brief, the rollers 32 separate the blanks from the array shown at 30 individually. The group of rollers 34 folds the bottom flap at the proper place, and one of the rollers, being heated, in cooperation with an adjacent roller, softens the adhesive and causes the bottom flap to be adhered to the side flaps. The rollers 35 as a group fold the top or seal flap, and deliver the envelope to the transfer mechanism 36, which in turn carries them to a table 36a for handing, boxing and the like.

It can be seen that the method employed entails the minimum of travel of the envelopes in any but a deeply overlapped array, and in particular, the application of all adhesive and subsequent drying is done with the envelopes overlapped without an intermediate step requiring serial motion of the envelopes through the various mechanisms.

In FIG. 2 there is shown in diagrammatic form a modification of the machine and method. The rhomboidal blanks 40 are delivered one at a time to the pairs of rollers 41, 42, 43 and 44, which successively operate on them to produce a properly cut and scored blank 45. The rollers 41 and 42 produce the corner cuts, the rollers 43 cut off the side flaps and bottom flaps, and produce the side scores. The rollers 44 produce the top and bottom scores. It will be appreciated that any other cutting operation, such as producing window openings, can be performed at this point if desired. The envelopes are then collated to produce an overlapping array as at 46. It is not necessary that the space 47 be as wide as shown, if the corner cuts are made, as they usually are, so that a pair of side flaps can be folded over the top flap of an adjacent envelope blank without creasing it. The space 47 in such a case need be only wide enough to prevent the side flaps from interfering with each other as they are folded in. It is not necessary that the seal flap fall short of the side flaps of the next forward blank, although it may be desirable to facilitate uniform action of the gummer. Any suitable means, such as the plowshare folder 48, is then, utilized to fold in the side flaps to produce the array of blanks 49. This array is then passed through the adhesive applying mechanism 50, which applies adhesive in a chevron shaped pattern to the outside of the side flaps of each blank. The adhesive can be any material used for immediate adherence of the parts to be joined, and need not be as in the first described embodiment, a material which loses its tackiness sufficiently to prevent adherence of adjacent blanks or transfer thereto.

After the application of adhesive to the side flaps, the blanks are separated by the rollers 51, and fed, one by one, to the folder 52, which takes each blank, folds the a collator at 53 arranges the blanks in an array as shown at 54, with the top flaps trailing and with the inside thereof at the bottom of the array. Rollers 55 then apply the seal adhesive, the adhesive being applied to the flaps in a continuous band by the roller 56. Subsequent to the application of the top flap adhesive, the blanks are slightly separated for drying, as set forth in connection with the embodiment shown in FIG. I, and delivered to a pair of rollers 57 for separation. The blanks are then transferred to the top flap folder 58, which delivers the now completed envelopes to a transfer Wheel 59, which in turn places them on a receiving table for boxing, banding or the like.

While the two methods and machines utilized have been described in some detail, it is to be understood that it is not intended that the invention be limited to such description, but that it be apprehended from the appended claims.

What is claimed is:

1. The method of making envelopes which includes, folding back the bottom flap, applying a reactivatable adhesive to the thus-exposed surface of the bottom flap of each blank, restoring the bottom flap to its former position, applying seal gum to the seal flap. folding the side and bottom flaps and reactivating the adhesive to secure the side and bottom flaps to each other.

2. The method in accordance with claim 1 including the step of collating the blanks in a lapped array and maintaining the array in lapped condition during application of adhesive to the bottom flap.

3. The method in accordance with claim 1 including the further step of folding the seal flap.

4. The method in accordance with claim 1 including the step of reactivating the adhesive applied to the bottom fiap prior to the step of folding the side and bottom fia s.

The method in accordance with claim 4 wherein the adhesive applied to the bottom flap is heat sensitive and said reactivating step includes applying heat to the adhesive.

6. The method in accordance with claim 4 wherein the adhesive applied to the bottom flap is remoistenable and said reactivating step includes applying a solvent to the adhesive.

7. The method in accordance with claim 4 wherein the adhesive applied to the bottom flap is remoistenable and said reactivating step includes applying water to the adhesive.

8. A method of forming envelopes from a stream of blanks each of which has a bottom flap, a pair of opposed side fiaps and a seal flap, said method comprising:

(a) applying adhesive to a marginal flap edge other than the seal flap;

(b) securing the side flaps to the bottom flaps;

(c) applying adhesive to the seal flaps; and

(d) reversing the position of one of the flaps of each blank other than the side flaps at one stage during the formation of the envelope.

9. The method in accordance with claim 8 wherein the adhesive is applied to the bottom flaps and the fiap reversing step comprises deflecting the bottom flaps in a direction opposite to the movement of the stream prior to the application of adhesive thereto.

10. The method in accordance with claim 9 including the step of collating the blanks in lapped array whereby deflection of the first bottom flap in the stream causes similar deflection of succeeding bottom flaps.

11. The method in accordance with claim 9 including the additional step of replacing the bottom flaps to their original position subsequent to applying adhesive thereto.

12. The method in accordance with claim 9 including the step of folding the seal flap subsequent to the application of adhesive thereto.

13. The method in accordance with claim 8 wherein the adhesive is applied to the side flaps and wherein the 5 flap reversing step comprises changing the position of the bottom and seal flaps end-to-end whereby the bottom flap is secured to the side flaps and the seal flaps are exposed for the application of adhesive thereto.

14. The method in accordance With claim 13 including the step of folding the seal flap subsequent to the application of adhesive thereto.

15. The method in accordance 'With claim 8 wherein the adhesive applied to the flaps other than the seal flaps is reactivatable and including the step of reactivating that adhesive prior to Securing the side flaps to the bottom flap.

6 16. The method in accordance with claim 15 wherein said reactivating step comprises applying heat.

17. The method in accordance with claim 15 wherein said reactivating step comprises applying a solvent.

18. The method in accordance With claim 15 wherein said reactivating step comprises applying water.

References Cited UNITED STATES PATENTS 2,983,201 5/1961 Winkler et al. 9662 BERNARD STICKNEY, Primary Examineir. 

